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<pre><span class="sourceLineNo">001</span>/*<a name="line.1"></a>
<span class="sourceLineNo">002</span> * Copyright (C) 2007 The Guava Authors<a name="line.2"></a>
<span class="sourceLineNo">003</span> *<a name="line.3"></a>
<span class="sourceLineNo">004</span> * Licensed under the Apache License, Version 2.0 (the "License");<a name="line.4"></a>
<span class="sourceLineNo">005</span> * you may not use this file except in compliance with the License.<a name="line.5"></a>
<span class="sourceLineNo">006</span> * You may obtain a copy of the License at<a name="line.6"></a>
<span class="sourceLineNo">007</span> *<a name="line.7"></a>
<span class="sourceLineNo">008</span> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.8"></a>
<span class="sourceLineNo">009</span> *<a name="line.9"></a>
<span class="sourceLineNo">010</span> * Unless required by applicable law or agreed to in writing, software<a name="line.10"></a>
<span class="sourceLineNo">011</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.11"></a>
<span class="sourceLineNo">012</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.12"></a>
<span class="sourceLineNo">013</span> * See the License for the specific language governing permissions and<a name="line.13"></a>
<span class="sourceLineNo">014</span> * limitations under the License.<a name="line.14"></a>
<span class="sourceLineNo">015</span> */<a name="line.15"></a>
<span class="sourceLineNo">016</span><a name="line.16"></a>
<span class="sourceLineNo">017</span>package com.google.common.collect;<a name="line.17"></a>
<span class="sourceLineNo">018</span><a name="line.18"></a>
<span class="sourceLineNo">019</span>import static com.google.common.base.Preconditions.checkArgument;<a name="line.19"></a>
<span class="sourceLineNo">020</span>import static com.google.common.base.Preconditions.checkNotNull;<a name="line.20"></a>
<span class="sourceLineNo">021</span><a name="line.21"></a>
<span class="sourceLineNo">022</span>import com.google.common.annotations.Beta;<a name="line.22"></a>
<span class="sourceLineNo">023</span>import com.google.common.annotations.GwtCompatible;<a name="line.23"></a>
<span class="sourceLineNo">024</span>import com.google.common.annotations.VisibleForTesting;<a name="line.24"></a>
<span class="sourceLineNo">025</span>import com.google.common.base.Function;<a name="line.25"></a>
<span class="sourceLineNo">026</span><a name="line.26"></a>
<span class="sourceLineNo">027</span>import java.util.ArrayList;<a name="line.27"></a>
<span class="sourceLineNo">028</span>import java.util.Arrays;<a name="line.28"></a>
<span class="sourceLineNo">029</span>import java.util.Collection;<a name="line.29"></a>
<span class="sourceLineNo">030</span>import java.util.Collections;<a name="line.30"></a>
<span class="sourceLineNo">031</span>import java.util.Comparator;<a name="line.31"></a>
<span class="sourceLineNo">032</span>import java.util.HashSet;<a name="line.32"></a>
<span class="sourceLineNo">033</span>import java.util.Iterator;<a name="line.33"></a>
<span class="sourceLineNo">034</span>import java.util.List;<a name="line.34"></a>
<span class="sourceLineNo">035</span>import java.util.Map;<a name="line.35"></a>
<span class="sourceLineNo">036</span>import java.util.NoSuchElementException;<a name="line.36"></a>
<span class="sourceLineNo">037</span>import java.util.SortedMap;<a name="line.37"></a>
<span class="sourceLineNo">038</span>import java.util.SortedSet;<a name="line.38"></a>
<span class="sourceLineNo">039</span>import java.util.TreeSet;<a name="line.39"></a>
<span class="sourceLineNo">040</span>import java.util.concurrent.atomic.AtomicInteger;<a name="line.40"></a>
<span class="sourceLineNo">041</span><a name="line.41"></a>
<span class="sourceLineNo">042</span>import javax.annotation.Nullable;<a name="line.42"></a>
<span class="sourceLineNo">043</span><a name="line.43"></a>
<span class="sourceLineNo">044</span>/**<a name="line.44"></a>
<span class="sourceLineNo">045</span> * A comparator, with additional methods to support common operations. This is<a name="line.45"></a>
<span class="sourceLineNo">046</span> * an "enriched" version of {@code Comparator}, in the same sense that {@link<a name="line.46"></a>
<span class="sourceLineNo">047</span> * FluentIterable} is an enriched {@link Iterable}). For example: &lt;pre&gt;   {@code<a name="line.47"></a>
<span class="sourceLineNo">048</span> *<a name="line.48"></a>
<span class="sourceLineNo">049</span> *   if (Ordering.from(comparator).reverse().isOrdered(list)) { ... }}&lt;/pre&gt;<a name="line.49"></a>
<span class="sourceLineNo">050</span> *<a name="line.50"></a>
<span class="sourceLineNo">051</span> * The {@link #from(Comparator)} method returns the equivalent {@code Ordering}<a name="line.51"></a>
<span class="sourceLineNo">052</span> * instance for a pre-existing comparator. You can also skip the comparator step<a name="line.52"></a>
<span class="sourceLineNo">053</span> * and extend {@code Ordering} directly: &lt;pre&gt;   {@code<a name="line.53"></a>
<span class="sourceLineNo">054</span> *<a name="line.54"></a>
<span class="sourceLineNo">055</span> *   Ordering&lt;String&gt; byLengthOrdering = new Ordering&lt;String&gt;() {<a name="line.55"></a>
<span class="sourceLineNo">056</span> *     public int compare(String left, String right) {<a name="line.56"></a>
<span class="sourceLineNo">057</span> *       return Ints.compare(left.length(), right.length());<a name="line.57"></a>
<span class="sourceLineNo">058</span> *     }<a name="line.58"></a>
<span class="sourceLineNo">059</span> *   };}&lt;/pre&gt;<a name="line.59"></a>
<span class="sourceLineNo">060</span> *<a name="line.60"></a>
<span class="sourceLineNo">061</span> * Except as noted, the orderings returned by the factory methods of this<a name="line.61"></a>
<span class="sourceLineNo">062</span> * class are serializable if and only if the provided instances that back them<a name="line.62"></a>
<span class="sourceLineNo">063</span> * are. For example, if {@code ordering} and {@code function} can themselves be<a name="line.63"></a>
<span class="sourceLineNo">064</span> * serialized, then {@code ordering.onResultOf(function)} can as well.<a name="line.64"></a>
<span class="sourceLineNo">065</span> *<a name="line.65"></a>
<span class="sourceLineNo">066</span> * &lt;p&gt;See the Guava User Guide article on &lt;a href=<a name="line.66"></a>
<span class="sourceLineNo">067</span> * "http://code.google.com/p/guava-libraries/wiki/OrderingExplained"&gt;<a name="line.67"></a>
<span class="sourceLineNo">068</span> * {@code Ordering}&lt;/a&gt;.<a name="line.68"></a>
<span class="sourceLineNo">069</span> *<a name="line.69"></a>
<span class="sourceLineNo">070</span> * @author Jesse Wilson<a name="line.70"></a>
<span class="sourceLineNo">071</span> * @author Kevin Bourrillion<a name="line.71"></a>
<span class="sourceLineNo">072</span> * @since 2.0 (imported from Google Collections Library)<a name="line.72"></a>
<span class="sourceLineNo">073</span> */<a name="line.73"></a>
<span class="sourceLineNo">074</span>@GwtCompatible<a name="line.74"></a>
<span class="sourceLineNo">075</span>public abstract class Ordering&lt;T&gt; implements Comparator&lt;T&gt; {<a name="line.75"></a>
<span class="sourceLineNo">076</span>  // Natural order<a name="line.76"></a>
<span class="sourceLineNo">077</span><a name="line.77"></a>
<span class="sourceLineNo">078</span>  /**<a name="line.78"></a>
<span class="sourceLineNo">079</span>   * Returns a serializable ordering that uses the natural order of the values.<a name="line.79"></a>
<span class="sourceLineNo">080</span>   * The ordering throws a {@link NullPointerException} when passed a null<a name="line.80"></a>
<span class="sourceLineNo">081</span>   * parameter.<a name="line.81"></a>
<span class="sourceLineNo">082</span>   *<a name="line.82"></a>
<span class="sourceLineNo">083</span>   * &lt;p&gt;The type specification is {@code &lt;C extends Comparable&gt;}, instead of<a name="line.83"></a>
<span class="sourceLineNo">084</span>   * the technically correct {@code &lt;C extends Comparable&lt;? super C&gt;&gt;}, to<a name="line.84"></a>
<span class="sourceLineNo">085</span>   * support legacy types from before Java 5.<a name="line.85"></a>
<span class="sourceLineNo">086</span>   */<a name="line.86"></a>
<span class="sourceLineNo">087</span>  @GwtCompatible(serializable = true)<a name="line.87"></a>
<span class="sourceLineNo">088</span>  @SuppressWarnings("unchecked") // TODO(kevinb): right way to explain this??<a name="line.88"></a>
<span class="sourceLineNo">089</span>  public static &lt;C extends Comparable&gt; Ordering&lt;C&gt; natural() {<a name="line.89"></a>
<span class="sourceLineNo">090</span>    return (Ordering&lt;C&gt;) NaturalOrdering.INSTANCE;<a name="line.90"></a>
<span class="sourceLineNo">091</span>  }<a name="line.91"></a>
<span class="sourceLineNo">092</span><a name="line.92"></a>
<span class="sourceLineNo">093</span>  // Static factories<a name="line.93"></a>
<span class="sourceLineNo">094</span><a name="line.94"></a>
<span class="sourceLineNo">095</span>  /**<a name="line.95"></a>
<span class="sourceLineNo">096</span>   * Returns an ordering based on an &lt;i&gt;existing&lt;/i&gt; comparator instance. Note<a name="line.96"></a>
<span class="sourceLineNo">097</span>   * that there's no need to create a &lt;i&gt;new&lt;/i&gt; comparator just to pass it in<a name="line.97"></a>
<span class="sourceLineNo">098</span>   * here; simply subclass {@code Ordering} and implement its {@code compareTo}<a name="line.98"></a>
<span class="sourceLineNo">099</span>   * method directly instead.<a name="line.99"></a>
<span class="sourceLineNo">100</span>   *<a name="line.100"></a>
<span class="sourceLineNo">101</span>   * @param comparator the comparator that defines the order<a name="line.101"></a>
<span class="sourceLineNo">102</span>   * @return comparator itself if it is already an {@code Ordering}; otherwise<a name="line.102"></a>
<span class="sourceLineNo">103</span>   *     an ordering that wraps that comparator<a name="line.103"></a>
<span class="sourceLineNo">104</span>   */<a name="line.104"></a>
<span class="sourceLineNo">105</span>  @GwtCompatible(serializable = true)<a name="line.105"></a>
<span class="sourceLineNo">106</span>  public static &lt;T&gt; Ordering&lt;T&gt; from(Comparator&lt;T&gt; comparator) {<a name="line.106"></a>
<span class="sourceLineNo">107</span>    return (comparator instanceof Ordering)<a name="line.107"></a>
<span class="sourceLineNo">108</span>        ? (Ordering&lt;T&gt;) comparator<a name="line.108"></a>
<span class="sourceLineNo">109</span>        : new ComparatorOrdering&lt;T&gt;(comparator);<a name="line.109"></a>
<span class="sourceLineNo">110</span>  }<a name="line.110"></a>
<span class="sourceLineNo">111</span><a name="line.111"></a>
<span class="sourceLineNo">112</span>  /**<a name="line.112"></a>
<span class="sourceLineNo">113</span>   * Simply returns its argument.<a name="line.113"></a>
<span class="sourceLineNo">114</span>   *<a name="line.114"></a>
<span class="sourceLineNo">115</span>   * @deprecated no need to use this<a name="line.115"></a>
<span class="sourceLineNo">116</span>   */<a name="line.116"></a>
<span class="sourceLineNo">117</span>  @GwtCompatible(serializable = true)<a name="line.117"></a>
<span class="sourceLineNo">118</span>  @Deprecated public static &lt;T&gt; Ordering&lt;T&gt; from(Ordering&lt;T&gt; ordering) {<a name="line.118"></a>
<span class="sourceLineNo">119</span>    return checkNotNull(ordering);<a name="line.119"></a>
<span class="sourceLineNo">120</span>  }<a name="line.120"></a>
<span class="sourceLineNo">121</span><a name="line.121"></a>
<span class="sourceLineNo">122</span>  /**<a name="line.122"></a>
<span class="sourceLineNo">123</span>   * Returns an ordering that compares objects according to the order in<a name="line.123"></a>
<span class="sourceLineNo">124</span>   * which they appear in the given list. Only objects present in the list<a name="line.124"></a>
<span class="sourceLineNo">125</span>   * (according to {@link Object#equals}) may be compared. This comparator<a name="line.125"></a>
<span class="sourceLineNo">126</span>   * imposes a "partial ordering" over the type {@code T}. Subsequent changes<a name="line.126"></a>
<span class="sourceLineNo">127</span>   * to the {@code valuesInOrder} list will have no effect on the returned<a name="line.127"></a>
<span class="sourceLineNo">128</span>   * comparator. Null values in the list are not supported.<a name="line.128"></a>
<span class="sourceLineNo">129</span>   *<a name="line.129"></a>
<span class="sourceLineNo">130</span>   * &lt;p&gt;The returned comparator throws an {@link ClassCastException} when it<a name="line.130"></a>
<span class="sourceLineNo">131</span>   * receives an input parameter that isn't among the provided values.<a name="line.131"></a>
<span class="sourceLineNo">132</span>   *<a name="line.132"></a>
<span class="sourceLineNo">133</span>   * &lt;p&gt;The generated comparator is serializable if all the provided values are<a name="line.133"></a>
<span class="sourceLineNo">134</span>   * serializable.<a name="line.134"></a>
<span class="sourceLineNo">135</span>   *<a name="line.135"></a>
<span class="sourceLineNo">136</span>   * @param valuesInOrder the values that the returned comparator will be able<a name="line.136"></a>
<span class="sourceLineNo">137</span>   *     to compare, in the order the comparator should induce<a name="line.137"></a>
<span class="sourceLineNo">138</span>   * @return the comparator described above<a name="line.138"></a>
<span class="sourceLineNo">139</span>   * @throws NullPointerException if any of the provided values is null<a name="line.139"></a>
<span class="sourceLineNo">140</span>   * @throws IllegalArgumentException if {@code valuesInOrder} contains any<a name="line.140"></a>
<span class="sourceLineNo">141</span>   *     duplicate values (according to {@link Object#equals})<a name="line.141"></a>
<span class="sourceLineNo">142</span>   */<a name="line.142"></a>
<span class="sourceLineNo">143</span>  @GwtCompatible(serializable = true)<a name="line.143"></a>
<span class="sourceLineNo">144</span>  public static &lt;T&gt; Ordering&lt;T&gt; explicit(List&lt;T&gt; valuesInOrder) {<a name="line.144"></a>
<span class="sourceLineNo">145</span>    return new ExplicitOrdering&lt;T&gt;(valuesInOrder);<a name="line.145"></a>
<span class="sourceLineNo">146</span>  }<a name="line.146"></a>
<span class="sourceLineNo">147</span><a name="line.147"></a>
<span class="sourceLineNo">148</span>  /**<a name="line.148"></a>
<span class="sourceLineNo">149</span>   * Returns an ordering that compares objects according to the order in<a name="line.149"></a>
<span class="sourceLineNo">150</span>   * which they are given to this method. Only objects present in the argument<a name="line.150"></a>
<span class="sourceLineNo">151</span>   * list (according to {@link Object#equals}) may be compared. This comparator<a name="line.151"></a>
<span class="sourceLineNo">152</span>   * imposes a "partial ordering" over the type {@code T}. Null values in the<a name="line.152"></a>
<span class="sourceLineNo">153</span>   * argument list are not supported.<a name="line.153"></a>
<span class="sourceLineNo">154</span>   *<a name="line.154"></a>
<span class="sourceLineNo">155</span>   * &lt;p&gt;The returned comparator throws a {@link ClassCastException} when it<a name="line.155"></a>
<span class="sourceLineNo">156</span>   * receives an input parameter that isn't among the provided values.<a name="line.156"></a>
<span class="sourceLineNo">157</span>   *<a name="line.157"></a>
<span class="sourceLineNo">158</span>   * &lt;p&gt;The generated comparator is serializable if all the provided values are<a name="line.158"></a>
<span class="sourceLineNo">159</span>   * serializable.<a name="line.159"></a>
<span class="sourceLineNo">160</span>   *<a name="line.160"></a>
<span class="sourceLineNo">161</span>   * @param leastValue the value which the returned comparator should consider<a name="line.161"></a>
<span class="sourceLineNo">162</span>   *     the "least" of all values<a name="line.162"></a>
<span class="sourceLineNo">163</span>   * @param remainingValuesInOrder the rest of the values that the returned<a name="line.163"></a>
<span class="sourceLineNo">164</span>   *     comparator will be able to compare, in the order the comparator should<a name="line.164"></a>
<span class="sourceLineNo">165</span>   *     follow<a name="line.165"></a>
<span class="sourceLineNo">166</span>   * @return the comparator described above<a name="line.166"></a>
<span class="sourceLineNo">167</span>   * @throws NullPointerException if any of the provided values is null<a name="line.167"></a>
<span class="sourceLineNo">168</span>   * @throws IllegalArgumentException if any duplicate values (according to<a name="line.168"></a>
<span class="sourceLineNo">169</span>   *     {@link Object#equals(Object)}) are present among the method arguments<a name="line.169"></a>
<span class="sourceLineNo">170</span>   */<a name="line.170"></a>
<span class="sourceLineNo">171</span>  @GwtCompatible(serializable = true)<a name="line.171"></a>
<span class="sourceLineNo">172</span>  public static &lt;T&gt; Ordering&lt;T&gt; explicit(<a name="line.172"></a>
<span class="sourceLineNo">173</span>      T leastValue, T... remainingValuesInOrder) {<a name="line.173"></a>
<span class="sourceLineNo">174</span>    return explicit(Lists.asList(leastValue, remainingValuesInOrder));<a name="line.174"></a>
<span class="sourceLineNo">175</span>  }<a name="line.175"></a>
<span class="sourceLineNo">176</span><a name="line.176"></a>
<span class="sourceLineNo">177</span>  // Ordering&lt;Object&gt; singletons<a name="line.177"></a>
<span class="sourceLineNo">178</span><a name="line.178"></a>
<span class="sourceLineNo">179</span>  /**<a name="line.179"></a>
<span class="sourceLineNo">180</span>   * Returns an ordering which treats all values as equal, indicating "no<a name="line.180"></a>
<span class="sourceLineNo">181</span>   * ordering." Passing this ordering to any &lt;i&gt;stable&lt;/i&gt; sort algorithm<a name="line.181"></a>
<span class="sourceLineNo">182</span>   * results in no change to the order of elements. Note especially that {@link<a name="line.182"></a>
<span class="sourceLineNo">183</span>   * #sortedCopy} and {@link #immutableSortedCopy} are stable, and in the<a name="line.183"></a>
<span class="sourceLineNo">184</span>   * returned instance these are implemented by simply copying the source list.<a name="line.184"></a>
<span class="sourceLineNo">185</span>   *<a name="line.185"></a>
<span class="sourceLineNo">186</span>   * &lt;p&gt;Example: &lt;pre&gt;   {@code<a name="line.186"></a>
<span class="sourceLineNo">187</span>   *<a name="line.187"></a>
<span class="sourceLineNo">188</span>   *   Ordering.allEqual().nullsLast().sortedCopy(<a name="line.188"></a>
<span class="sourceLineNo">189</span>   *       asList(t, null, e, s, null, t, null))}&lt;/pre&gt;<a name="line.189"></a>
<span class="sourceLineNo">190</span>   *<a name="line.190"></a>
<span class="sourceLineNo">191</span>   * Assuming {@code t}, {@code e} and {@code s} are non-null, this returns<a name="line.191"></a>
<span class="sourceLineNo">192</span>   * {@code [t, e, s, t, null, null, null]} regardlesss of the true comparison<a name="line.192"></a>
<span class="sourceLineNo">193</span>   * order of those three values (which might not even implement {@link<a name="line.193"></a>
<span class="sourceLineNo">194</span>   * Comparable} at all).<a name="line.194"></a>
<span class="sourceLineNo">195</span>   *<a name="line.195"></a>
<span class="sourceLineNo">196</span>   * &lt;p&gt;&lt;b&gt;Warning:&lt;/b&gt; by definition, this comparator is not &lt;i&gt;consistent with<a name="line.196"></a>
<span class="sourceLineNo">197</span>   * equals&lt;/i&gt; (as defined {@linkplain Comparator here}). Avoid its use in<a name="line.197"></a>
<span class="sourceLineNo">198</span>   * APIs, such as {@link TreeSet#TreeSet(Comparator)}, where such consistency<a name="line.198"></a>
<span class="sourceLineNo">199</span>   * is expected.<a name="line.199"></a>
<span class="sourceLineNo">200</span>   *<a name="line.200"></a>
<span class="sourceLineNo">201</span>   * &lt;p&gt;The returned comparator is serializable.<a name="line.201"></a>
<span class="sourceLineNo">202</span>   */<a name="line.202"></a>
<span class="sourceLineNo">203</span>  @GwtCompatible(serializable = true)<a name="line.203"></a>
<span class="sourceLineNo">204</span>  @SuppressWarnings("unchecked")<a name="line.204"></a>
<span class="sourceLineNo">205</span>  public static Ordering&lt;Object&gt; allEqual() {<a name="line.205"></a>
<span class="sourceLineNo">206</span>    return AllEqualOrdering.INSTANCE;<a name="line.206"></a>
<span class="sourceLineNo">207</span>  }<a name="line.207"></a>
<span class="sourceLineNo">208</span><a name="line.208"></a>
<span class="sourceLineNo">209</span>  /**<a name="line.209"></a>
<span class="sourceLineNo">210</span>   * Returns an ordering that compares objects by the natural ordering of their<a name="line.210"></a>
<span class="sourceLineNo">211</span>   * string representations as returned by {@code toString()}. It does not<a name="line.211"></a>
<span class="sourceLineNo">212</span>   * support null values.<a name="line.212"></a>
<span class="sourceLineNo">213</span>   *<a name="line.213"></a>
<span class="sourceLineNo">214</span>   * &lt;p&gt;The comparator is serializable.<a name="line.214"></a>
<span class="sourceLineNo">215</span>   */<a name="line.215"></a>
<span class="sourceLineNo">216</span>  @GwtCompatible(serializable = true)<a name="line.216"></a>
<span class="sourceLineNo">217</span>  public static Ordering&lt;Object&gt; usingToString() {<a name="line.217"></a>
<span class="sourceLineNo">218</span>    return UsingToStringOrdering.INSTANCE;<a name="line.218"></a>
<span class="sourceLineNo">219</span>  }<a name="line.219"></a>
<span class="sourceLineNo">220</span><a name="line.220"></a>
<span class="sourceLineNo">221</span>  /**<a name="line.221"></a>
<span class="sourceLineNo">222</span>   * Returns an arbitrary ordering over all objects, for which {@code compare(a,<a name="line.222"></a>
<span class="sourceLineNo">223</span>   * b) == 0} implies {@code a == b} (identity equality). There is no meaning<a name="line.223"></a>
<span class="sourceLineNo">224</span>   * whatsoever to the order imposed, but it is constant for the life of the VM.<a name="line.224"></a>
<span class="sourceLineNo">225</span>   *<a name="line.225"></a>
<span class="sourceLineNo">226</span>   * &lt;p&gt;Because the ordering is identity-based, it is not "consistent with<a name="line.226"></a>
<span class="sourceLineNo">227</span>   * {@link Object#equals(Object)}" as defined by {@link Comparator}. Use<a name="line.227"></a>
<span class="sourceLineNo">228</span>   * caution when building a {@link SortedSet} or {@link SortedMap} from it, as<a name="line.228"></a>
<span class="sourceLineNo">229</span>   * the resulting collection will not behave exactly according to spec.<a name="line.229"></a>
<span class="sourceLineNo">230</span>   *<a name="line.230"></a>
<span class="sourceLineNo">231</span>   * &lt;p&gt;This ordering is not serializable, as its implementation relies on<a name="line.231"></a>
<span class="sourceLineNo">232</span>   * {@link System#identityHashCode(Object)}, so its behavior cannot be<a name="line.232"></a>
<span class="sourceLineNo">233</span>   * preserved across serialization.<a name="line.233"></a>
<span class="sourceLineNo">234</span>   *<a name="line.234"></a>
<span class="sourceLineNo">235</span>   * @since 2.0<a name="line.235"></a>
<span class="sourceLineNo">236</span>   */<a name="line.236"></a>
<span class="sourceLineNo">237</span>  public static Ordering&lt;Object&gt; arbitrary() {<a name="line.237"></a>
<span class="sourceLineNo">238</span>    return ArbitraryOrderingHolder.ARBITRARY_ORDERING;<a name="line.238"></a>
<span class="sourceLineNo">239</span>  }<a name="line.239"></a>
<span class="sourceLineNo">240</span><a name="line.240"></a>
<span class="sourceLineNo">241</span>  private static class ArbitraryOrderingHolder {<a name="line.241"></a>
<span class="sourceLineNo">242</span>    static final Ordering&lt;Object&gt; ARBITRARY_ORDERING = new ArbitraryOrdering();<a name="line.242"></a>
<span class="sourceLineNo">243</span>  }<a name="line.243"></a>
<span class="sourceLineNo">244</span><a name="line.244"></a>
<span class="sourceLineNo">245</span>  @VisibleForTesting static class ArbitraryOrdering extends Ordering&lt;Object&gt; {<a name="line.245"></a>
<span class="sourceLineNo">246</span>    @SuppressWarnings("deprecation") // TODO(kevinb): ?<a name="line.246"></a>
<span class="sourceLineNo">247</span>    private Map&lt;Object, Integer&gt; uids =<a name="line.247"></a>
<span class="sourceLineNo">248</span>        Platform.tryWeakKeys(new MapMaker()).makeComputingMap(<a name="line.248"></a>
<span class="sourceLineNo">249</span>            new Function&lt;Object, Integer&gt;() {<a name="line.249"></a>
<span class="sourceLineNo">250</span>              final AtomicInteger counter = new AtomicInteger(0);<a name="line.250"></a>
<span class="sourceLineNo">251</span>              @Override<a name="line.251"></a>
<span class="sourceLineNo">252</span>              public Integer apply(Object from) {<a name="line.252"></a>
<span class="sourceLineNo">253</span>                return counter.getAndIncrement();<a name="line.253"></a>
<span class="sourceLineNo">254</span>              }<a name="line.254"></a>
<span class="sourceLineNo">255</span>            });<a name="line.255"></a>
<span class="sourceLineNo">256</span><a name="line.256"></a>
<span class="sourceLineNo">257</span>    @Override public int compare(Object left, Object right) {<a name="line.257"></a>
<span class="sourceLineNo">258</span>      if (left == right) {<a name="line.258"></a>
<span class="sourceLineNo">259</span>        return 0;<a name="line.259"></a>
<span class="sourceLineNo">260</span>      } else if (left == null) {<a name="line.260"></a>
<span class="sourceLineNo">261</span>        return -1;<a name="line.261"></a>
<span class="sourceLineNo">262</span>      } else if (right == null) {<a name="line.262"></a>
<span class="sourceLineNo">263</span>        return 1;<a name="line.263"></a>
<span class="sourceLineNo">264</span>      }<a name="line.264"></a>
<span class="sourceLineNo">265</span>      int leftCode = identityHashCode(left);<a name="line.265"></a>
<span class="sourceLineNo">266</span>      int rightCode = identityHashCode(right);<a name="line.266"></a>
<span class="sourceLineNo">267</span>      if (leftCode != rightCode) {<a name="line.267"></a>
<span class="sourceLineNo">268</span>        return leftCode &lt; rightCode ? -1 : 1;<a name="line.268"></a>
<span class="sourceLineNo">269</span>      }<a name="line.269"></a>
<span class="sourceLineNo">270</span><a name="line.270"></a>
<span class="sourceLineNo">271</span>      // identityHashCode collision (rare, but not as rare as you'd think)<a name="line.271"></a>
<span class="sourceLineNo">272</span>      int result = uids.get(left).compareTo(uids.get(right));<a name="line.272"></a>
<span class="sourceLineNo">273</span>      if (result == 0) {<a name="line.273"></a>
<span class="sourceLineNo">274</span>        throw new AssertionError(); // extremely, extremely unlikely.<a name="line.274"></a>
<span class="sourceLineNo">275</span>      }<a name="line.275"></a>
<span class="sourceLineNo">276</span>      return result;<a name="line.276"></a>
<span class="sourceLineNo">277</span>    }<a name="line.277"></a>
<span class="sourceLineNo">278</span><a name="line.278"></a>
<span class="sourceLineNo">279</span>    @Override public String toString() {<a name="line.279"></a>
<span class="sourceLineNo">280</span>      return "Ordering.arbitrary()";<a name="line.280"></a>
<span class="sourceLineNo">281</span>    }<a name="line.281"></a>
<span class="sourceLineNo">282</span><a name="line.282"></a>
<span class="sourceLineNo">283</span>    /*<a name="line.283"></a>
<span class="sourceLineNo">284</span>     * We need to be able to mock identityHashCode() calls for tests, because it<a name="line.284"></a>
<span class="sourceLineNo">285</span>     * can take 1-10 seconds to find colliding objects. Mocking frameworks that<a name="line.285"></a>
<span class="sourceLineNo">286</span>     * can do magic to mock static method calls still can't do so for a system<a name="line.286"></a>
<span class="sourceLineNo">287</span>     * class, so we need the indirection. In production, Hotspot should still<a name="line.287"></a>
<span class="sourceLineNo">288</span>     * recognize that the call is 1-morphic and should still be willing to<a name="line.288"></a>
<span class="sourceLineNo">289</span>     * inline it if necessary.<a name="line.289"></a>
<span class="sourceLineNo">290</span>     */<a name="line.290"></a>
<span class="sourceLineNo">291</span>    int identityHashCode(Object object) {<a name="line.291"></a>
<span class="sourceLineNo">292</span>      return System.identityHashCode(object);<a name="line.292"></a>
<span class="sourceLineNo">293</span>    }<a name="line.293"></a>
<span class="sourceLineNo">294</span>  }<a name="line.294"></a>
<span class="sourceLineNo">295</span><a name="line.295"></a>
<span class="sourceLineNo">296</span>  // Constructor<a name="line.296"></a>
<span class="sourceLineNo">297</span><a name="line.297"></a>
<span class="sourceLineNo">298</span>  /**<a name="line.298"></a>
<span class="sourceLineNo">299</span>   * Constructs a new instance of this class (only invokable by the subclass<a name="line.299"></a>
<span class="sourceLineNo">300</span>   * constructor, typically implicit).<a name="line.300"></a>
<span class="sourceLineNo">301</span>   */<a name="line.301"></a>
<span class="sourceLineNo">302</span>  protected Ordering() {}<a name="line.302"></a>
<span class="sourceLineNo">303</span><a name="line.303"></a>
<span class="sourceLineNo">304</span>  // Instance-based factories (and any static equivalents)<a name="line.304"></a>
<span class="sourceLineNo">305</span><a name="line.305"></a>
<span class="sourceLineNo">306</span>  /**<a name="line.306"></a>
<span class="sourceLineNo">307</span>   * Returns the reverse of this ordering; the {@code Ordering} equivalent to<a name="line.307"></a>
<span class="sourceLineNo">308</span>   * {@link Collections#reverseOrder(Comparator)}.<a name="line.308"></a>
<span class="sourceLineNo">309</span>   */<a name="line.309"></a>
<span class="sourceLineNo">310</span>  // type parameter &lt;S&gt; lets us avoid the extra &lt;String&gt; in statements like:<a name="line.310"></a>
<span class="sourceLineNo">311</span>  // Ordering&lt;String&gt; o = Ordering.&lt;String&gt;natural().reverse();<a name="line.311"></a>
<span class="sourceLineNo">312</span>  @GwtCompatible(serializable = true)<a name="line.312"></a>
<span class="sourceLineNo">313</span>  public &lt;S extends T&gt; Ordering&lt;S&gt; reverse() {<a name="line.313"></a>
<span class="sourceLineNo">314</span>    return new ReverseOrdering&lt;S&gt;(this);<a name="line.314"></a>
<span class="sourceLineNo">315</span>  }<a name="line.315"></a>
<span class="sourceLineNo">316</span><a name="line.316"></a>
<span class="sourceLineNo">317</span>  /**<a name="line.317"></a>
<span class="sourceLineNo">318</span>   * Returns an ordering that treats {@code null} as less than all other values<a name="line.318"></a>
<span class="sourceLineNo">319</span>   * and uses {@code this} to compare non-null values.<a name="line.319"></a>
<span class="sourceLineNo">320</span>   */<a name="line.320"></a>
<span class="sourceLineNo">321</span>  // type parameter &lt;S&gt; lets us avoid the extra &lt;String&gt; in statements like:<a name="line.321"></a>
<span class="sourceLineNo">322</span>  // Ordering&lt;String&gt; o = Ordering.&lt;String&gt;natural().nullsFirst();<a name="line.322"></a>
<span class="sourceLineNo">323</span>  @GwtCompatible(serializable = true)<a name="line.323"></a>
<span class="sourceLineNo">324</span>  public &lt;S extends T&gt; Ordering&lt;S&gt; nullsFirst() {<a name="line.324"></a>
<span class="sourceLineNo">325</span>    return new NullsFirstOrdering&lt;S&gt;(this);<a name="line.325"></a>
<span class="sourceLineNo">326</span>  }<a name="line.326"></a>
<span class="sourceLineNo">327</span><a name="line.327"></a>
<span class="sourceLineNo">328</span>  /**<a name="line.328"></a>
<span class="sourceLineNo">329</span>   * Returns an ordering that treats {@code null} as greater than all other<a name="line.329"></a>
<span class="sourceLineNo">330</span>   * values and uses this ordering to compare non-null values.<a name="line.330"></a>
<span class="sourceLineNo">331</span>   */<a name="line.331"></a>
<span class="sourceLineNo">332</span>  // type parameter &lt;S&gt; lets us avoid the extra &lt;String&gt; in statements like:<a name="line.332"></a>
<span class="sourceLineNo">333</span>  // Ordering&lt;String&gt; o = Ordering.&lt;String&gt;natural().nullsLast();<a name="line.333"></a>
<span class="sourceLineNo">334</span>  @GwtCompatible(serializable = true)<a name="line.334"></a>
<span class="sourceLineNo">335</span>  public &lt;S extends T&gt; Ordering&lt;S&gt; nullsLast() {<a name="line.335"></a>
<span class="sourceLineNo">336</span>    return new NullsLastOrdering&lt;S&gt;(this);<a name="line.336"></a>
<span class="sourceLineNo">337</span>  }<a name="line.337"></a>
<span class="sourceLineNo">338</span><a name="line.338"></a>
<span class="sourceLineNo">339</span>  /**<a name="line.339"></a>
<span class="sourceLineNo">340</span>   * Returns a new ordering on {@code F} which orders elements by first applying<a name="line.340"></a>
<span class="sourceLineNo">341</span>   * a function to them, then comparing those results using {@code this}. For<a name="line.341"></a>
<span class="sourceLineNo">342</span>   * example, to compare objects by their string forms, in a case-insensitive<a name="line.342"></a>
<span class="sourceLineNo">343</span>   * manner, use: &lt;pre&gt;   {@code<a name="line.343"></a>
<span class="sourceLineNo">344</span>   *<a name="line.344"></a>
<span class="sourceLineNo">345</span>   *   Ordering.from(String.CASE_INSENSITIVE_ORDER)<a name="line.345"></a>
<span class="sourceLineNo">346</span>   *       .onResultOf(Functions.toStringFunction())}&lt;/pre&gt;<a name="line.346"></a>
<span class="sourceLineNo">347</span>   */<a name="line.347"></a>
<span class="sourceLineNo">348</span>  @GwtCompatible(serializable = true)<a name="line.348"></a>
<span class="sourceLineNo">349</span>  public &lt;F&gt; Ordering&lt;F&gt; onResultOf(Function&lt;F, ? extends T&gt; function) {<a name="line.349"></a>
<span class="sourceLineNo">350</span>    return new ByFunctionOrdering&lt;F, T&gt;(function, this);<a name="line.350"></a>
<span class="sourceLineNo">351</span>  }<a name="line.351"></a>
<span class="sourceLineNo">352</span><a name="line.352"></a>
<span class="sourceLineNo">353</span>  /**<a name="line.353"></a>
<span class="sourceLineNo">354</span>   * Returns an ordering which first uses the ordering {@code this}, but which<a name="line.354"></a>
<span class="sourceLineNo">355</span>   * in the event of a "tie", then delegates to {@code secondaryComparator}.<a name="line.355"></a>
<span class="sourceLineNo">356</span>   * For example, to sort a bug list first by status and second by priority, you<a name="line.356"></a>
<span class="sourceLineNo">357</span>   * might use {@code byStatus.compound(byPriority)}. For a compound ordering<a name="line.357"></a>
<span class="sourceLineNo">358</span>   * with three or more components, simply chain multiple calls to this method.<a name="line.358"></a>
<span class="sourceLineNo">359</span>   *<a name="line.359"></a>
<span class="sourceLineNo">360</span>   * &lt;p&gt;An ordering produced by this method, or a chain of calls to this method,<a name="line.360"></a>
<span class="sourceLineNo">361</span>   * is equivalent to one created using {@link Ordering#compound(Iterable)} on<a name="line.361"></a>
<span class="sourceLineNo">362</span>   * the same component comparators.<a name="line.362"></a>
<span class="sourceLineNo">363</span>   */<a name="line.363"></a>
<span class="sourceLineNo">364</span>  @GwtCompatible(serializable = true)<a name="line.364"></a>
<span class="sourceLineNo">365</span>  public &lt;U extends T&gt; Ordering&lt;U&gt; compound(<a name="line.365"></a>
<span class="sourceLineNo">366</span>      Comparator&lt;? super U&gt; secondaryComparator) {<a name="line.366"></a>
<span class="sourceLineNo">367</span>    return new CompoundOrdering&lt;U&gt;(this, checkNotNull(secondaryComparator));<a name="line.367"></a>
<span class="sourceLineNo">368</span>  }<a name="line.368"></a>
<span class="sourceLineNo">369</span><a name="line.369"></a>
<span class="sourceLineNo">370</span>  /**<a name="line.370"></a>
<span class="sourceLineNo">371</span>   * Returns an ordering which tries each given comparator in order until a<a name="line.371"></a>
<span class="sourceLineNo">372</span>   * non-zero result is found, returning that result, and returning zero only if<a name="line.372"></a>
<span class="sourceLineNo">373</span>   * all comparators return zero. The returned ordering is based on the state of<a name="line.373"></a>
<span class="sourceLineNo">374</span>   * the {@code comparators} iterable at the time it was provided to this<a name="line.374"></a>
<span class="sourceLineNo">375</span>   * method.<a name="line.375"></a>
<span class="sourceLineNo">376</span>   *<a name="line.376"></a>
<span class="sourceLineNo">377</span>   * &lt;p&gt;The returned ordering is equivalent to that produced using {@code<a name="line.377"></a>
<span class="sourceLineNo">378</span>   * Ordering.from(comp1).compound(comp2).compound(comp3) . . .}.<a name="line.378"></a>
<span class="sourceLineNo">379</span>   *<a name="line.379"></a>
<span class="sourceLineNo">380</span>   * &lt;p&gt;&lt;b&gt;Warning:&lt;/b&gt; Supplying an argument with undefined iteration order,<a name="line.380"></a>
<span class="sourceLineNo">381</span>   * such as a {@link HashSet}, will produce non-deterministic results.<a name="line.381"></a>
<span class="sourceLineNo">382</span>   *<a name="line.382"></a>
<span class="sourceLineNo">383</span>   * @param comparators the comparators to try in order<a name="line.383"></a>
<span class="sourceLineNo">384</span>   */<a name="line.384"></a>
<span class="sourceLineNo">385</span>  @GwtCompatible(serializable = true)<a name="line.385"></a>
<span class="sourceLineNo">386</span>  public static &lt;T&gt; Ordering&lt;T&gt; compound(<a name="line.386"></a>
<span class="sourceLineNo">387</span>      Iterable&lt;? extends Comparator&lt;? super T&gt;&gt; comparators) {<a name="line.387"></a>
<span class="sourceLineNo">388</span>    return new CompoundOrdering&lt;T&gt;(comparators);<a name="line.388"></a>
<span class="sourceLineNo">389</span>  }<a name="line.389"></a>
<span class="sourceLineNo">390</span><a name="line.390"></a>
<span class="sourceLineNo">391</span>  /**<a name="line.391"></a>
<span class="sourceLineNo">392</span>   * Returns a new ordering which sorts iterables by comparing corresponding<a name="line.392"></a>
<span class="sourceLineNo">393</span>   * elements pairwise until a nonzero result is found; imposes "dictionary<a name="line.393"></a>
<span class="sourceLineNo">394</span>   * order". If the end of one iterable is reached, but not the other, the<a name="line.394"></a>
<span class="sourceLineNo">395</span>   * shorter iterable is considered to be less than the longer one. For example,<a name="line.395"></a>
<span class="sourceLineNo">396</span>   * a lexicographical natural ordering over integers considers {@code<a name="line.396"></a>
<span class="sourceLineNo">397</span>   * [] &lt; [1] &lt; [1, 1] &lt; [1, 2] &lt; [2]}.<a name="line.397"></a>
<span class="sourceLineNo">398</span>   *<a name="line.398"></a>
<span class="sourceLineNo">399</span>   * &lt;p&gt;Note that {@code ordering.lexicographical().reverse()} is not<a name="line.399"></a>
<span class="sourceLineNo">400</span>   * equivalent to {@code ordering.reverse().lexicographical()} (consider how<a name="line.400"></a>
<span class="sourceLineNo">401</span>   * each would order {@code [1]} and {@code [1, 1]}).<a name="line.401"></a>
<span class="sourceLineNo">402</span>   *<a name="line.402"></a>
<span class="sourceLineNo">403</span>   * @since 2.0<a name="line.403"></a>
<span class="sourceLineNo">404</span>   */<a name="line.404"></a>
<span class="sourceLineNo">405</span>  @GwtCompatible(serializable = true)<a name="line.405"></a>
<span class="sourceLineNo">406</span>  // type parameter &lt;S&gt; lets us avoid the extra &lt;String&gt; in statements like:<a name="line.406"></a>
<span class="sourceLineNo">407</span>  // Ordering&lt;Iterable&lt;String&gt;&gt; o =<a name="line.407"></a>
<span class="sourceLineNo">408</span>  //     Ordering.&lt;String&gt;natural().lexicographical();<a name="line.408"></a>
<span class="sourceLineNo">409</span>  public &lt;S extends T&gt; Ordering&lt;Iterable&lt;S&gt;&gt; lexicographical() {<a name="line.409"></a>
<span class="sourceLineNo">410</span>    /*<a name="line.410"></a>
<span class="sourceLineNo">411</span>     * Note that technically the returned ordering should be capable of<a name="line.411"></a>
<span class="sourceLineNo">412</span>     * handling not just {@code Iterable&lt;S&gt;} instances, but also any {@code<a name="line.412"></a>
<span class="sourceLineNo">413</span>     * Iterable&lt;? extends S&gt;}. However, the need for this comes up so rarely<a name="line.413"></a>
<span class="sourceLineNo">414</span>     * that it doesn't justify making everyone else deal with the very ugly<a name="line.414"></a>
<span class="sourceLineNo">415</span>     * wildcard.<a name="line.415"></a>
<span class="sourceLineNo">416</span>     */<a name="line.416"></a>
<span class="sourceLineNo">417</span>    return new LexicographicalOrdering&lt;S&gt;(this);<a name="line.417"></a>
<span class="sourceLineNo">418</span>  }<a name="line.418"></a>
<span class="sourceLineNo">419</span><a name="line.419"></a>
<span class="sourceLineNo">420</span>  // Regular instance methods<a name="line.420"></a>
<span class="sourceLineNo">421</span><a name="line.421"></a>
<span class="sourceLineNo">422</span>  // Override to add @Nullable<a name="line.422"></a>
<span class="sourceLineNo">423</span>  @Override public abstract int compare(@Nullable T left, @Nullable T right);<a name="line.423"></a>
<span class="sourceLineNo">424</span><a name="line.424"></a>
<span class="sourceLineNo">425</span>  /**<a name="line.425"></a>
<span class="sourceLineNo">426</span>   * Returns the least of the specified values according to this ordering. If<a name="line.426"></a>
<span class="sourceLineNo">427</span>   * there are multiple least values, the first of those is returned. The<a name="line.427"></a>
<span class="sourceLineNo">428</span>   * iterator will be left exhausted: its {@code hasNext()} method will return<a name="line.428"></a>
<span class="sourceLineNo">429</span>   * {@code false}.<a name="line.429"></a>
<span class="sourceLineNo">430</span>   *<a name="line.430"></a>
<span class="sourceLineNo">431</span>   * @param iterator the iterator whose minimum element is to be determined<a name="line.431"></a>
<span class="sourceLineNo">432</span>   * @throws NoSuchElementException if {@code iterator} is empty<a name="line.432"></a>
<span class="sourceLineNo">433</span>   * @throws ClassCastException if the parameters are not &lt;i&gt;mutually<a name="line.433"></a>
<span class="sourceLineNo">434</span>   *     comparable&lt;/i&gt; under this ordering.<a name="line.434"></a>
<span class="sourceLineNo">435</span>   *<a name="line.435"></a>
<span class="sourceLineNo">436</span>   * @since 11.0<a name="line.436"></a>
<span class="sourceLineNo">437</span>   */<a name="line.437"></a>
<span class="sourceLineNo">438</span>  @Beta<a name="line.438"></a>
<span class="sourceLineNo">439</span>  public &lt;E extends T&gt; E min(Iterator&lt;E&gt; iterator) {<a name="line.439"></a>
<span class="sourceLineNo">440</span>    // let this throw NoSuchElementException as necessary<a name="line.440"></a>
<span class="sourceLineNo">441</span>    E minSoFar = iterator.next();<a name="line.441"></a>
<span class="sourceLineNo">442</span><a name="line.442"></a>
<span class="sourceLineNo">443</span>    while (iterator.hasNext()) {<a name="line.443"></a>
<span class="sourceLineNo">444</span>      minSoFar = min(minSoFar, iterator.next());<a name="line.444"></a>
<span class="sourceLineNo">445</span>    }<a name="line.445"></a>
<span class="sourceLineNo">446</span><a name="line.446"></a>
<span class="sourceLineNo">447</span>    return minSoFar;<a name="line.447"></a>
<span class="sourceLineNo">448</span>  }<a name="line.448"></a>
<span class="sourceLineNo">449</span><a name="line.449"></a>
<span class="sourceLineNo">450</span>  /**<a name="line.450"></a>
<span class="sourceLineNo">451</span>   * Returns the least of the specified values according to this ordering. If<a name="line.451"></a>
<span class="sourceLineNo">452</span>   * there are multiple least values, the first of those is returned.<a name="line.452"></a>
<span class="sourceLineNo">453</span>   *<a name="line.453"></a>
<span class="sourceLineNo">454</span>   * @param iterable the iterable whose minimum element is to be determined<a name="line.454"></a>
<span class="sourceLineNo">455</span>   * @throws NoSuchElementException if {@code iterable} is empty<a name="line.455"></a>
<span class="sourceLineNo">456</span>   * @throws ClassCastException if the parameters are not &lt;i&gt;mutually<a name="line.456"></a>
<span class="sourceLineNo">457</span>   *     comparable&lt;/i&gt; under this ordering.<a name="line.457"></a>
<span class="sourceLineNo">458</span>   */<a name="line.458"></a>
<span class="sourceLineNo">459</span>  public &lt;E extends T&gt; E min(Iterable&lt;E&gt; iterable) {<a name="line.459"></a>
<span class="sourceLineNo">460</span>    return min(iterable.iterator());<a name="line.460"></a>
<span class="sourceLineNo">461</span>  }<a name="line.461"></a>
<span class="sourceLineNo">462</span><a name="line.462"></a>
<span class="sourceLineNo">463</span>  /**<a name="line.463"></a>
<span class="sourceLineNo">464</span>   * Returns the lesser of the two values according to this ordering. If the<a name="line.464"></a>
<span class="sourceLineNo">465</span>   * values compare as 0, the first is returned.<a name="line.465"></a>
<span class="sourceLineNo">466</span>   *<a name="line.466"></a>
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<span class="sourceLineNo">531</span>   * @param iterable the iterable whose maximum element is to be determined<a name="line.531"></a>
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<span class="sourceLineNo">543</span>   *<a name="line.543"></a>
<span class="sourceLineNo">544</span>   * &lt;p&gt;&lt;b&gt;Implementation note:&lt;/b&gt; this method is invoked by the default<a name="line.544"></a>
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<span class="sourceLineNo">563</span>   * @param c value to compare<a name="line.563"></a>
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<span class="sourceLineNo">581</span>   * this ordering, in order from least to greatest.  If there are fewer than<a name="line.581"></a>
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<span class="sourceLineNo">595</span>    if (iterable instanceof Collection) {<a name="line.595"></a>
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<span class="sourceLineNo">597</span>      if (collection.size() &lt;= 2L * k) {<a name="line.597"></a>
<span class="sourceLineNo">598</span>        // In this case, just dumping the collection to an array and sorting is<a name="line.598"></a>
<span class="sourceLineNo">599</span>        // faster than using the implementation for Iterator, which is<a name="line.599"></a>
<span class="sourceLineNo">600</span>        // specialized for k much smaller than n.<a name="line.600"></a>
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<span class="sourceLineNo">616</span>   * this ordering, in order from least to greatest.  If there are fewer than<a name="line.616"></a>
<span class="sourceLineNo">617</span>   * {@code k} elements present, all will be included.<a name="line.617"></a>
<span class="sourceLineNo">618</span>   *<a name="line.618"></a>
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<span class="sourceLineNo">623</span>   * @return an immutable {@code RandomAccess} list of the {@code k} least<a name="line.623"></a>
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<span class="sourceLineNo">807</span>   *<a name="line.807"></a>
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<span class="sourceLineNo">827</span>   * greater than or equal to the element that preceded it, according to this<a name="line.827"></a>
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<span class="sourceLineNo">879</span>  /**<a name="line.879"></a>
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<span class="sourceLineNo">881</span>   * Ordering#explicit(Object, Object[])} comparator when comparing a value<a name="line.881"></a>
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<span class="sourceLineNo">887</span>  static class IncomparableValueException extends ClassCastException {<a name="line.887"></a>
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<span class="sourceLineNo">889</span><a name="line.889"></a>
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<span class="sourceLineNo">892</span>      this.value = value;<a name="line.892"></a>
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<span class="sourceLineNo">897</span><a name="line.897"></a>
<span class="sourceLineNo">898</span>  // Never make these public<a name="line.898"></a>
<span class="sourceLineNo">899</span>  static final int LEFT_IS_GREATER = 1;<a name="line.899"></a>
<span class="sourceLineNo">900</span>  static final int RIGHT_IS_GREATER = -1;<a name="line.900"></a>
<span class="sourceLineNo">901</span>}<a name="line.901"></a>




























































</pre>
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